Seroatlas · Human Serome Atlas

ST8SIA1

Alpha-N-acetylneuraminide alpha-2,8-sialyltransferase

Also known as: SIA8A_HUMAN, SIAT8, SIAT8A

Cross-references: UniProt · Ensembl · Human Protein Atlas · GeneCards · NCBI Gene

Protein identityUniProt · HPA

UniProt accession
Q92185
Gene
ST8SIA1
Ensembl
ENSG00000111728
Chromosome
12
Canonical length
356 aa
Protein class
Enzymes, Metabolic proteins, Predicted intracellular proteins, Predicted membrane proteins

OverviewNCBI Gene

Gangliosides are membrane-bound glycosphingolipids containing sialic acid. Ganglioside GD3 is known to be important for cell adhesion and growth of cultured malignant cells. The protein encoded by this gene is a type II membrane protein that catalyzes the transfer of sialic acid from CMP-sialic acid to GM3 to produce gangliosides GD3 and GT3. The encoded protein may be found in the Golgi apparatus and is a member of glycosyltransferase family 29. Alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Jan 2015]

Canonical amino-acid sequenceUniProt

356 residues, UniProt reviewed canonical sequence.

>Q92185|ST8SIA1
     1  MSPCGRARRQ TSRGAMAVLA WKFPRTRLPM GASALCVVVL CWLYIFPVYR LPNEKEIVQG
    61  VLQQGTAWRR NQTAARAFRK QMEDCCDPAH LFAMTKMNSP MGKSMWYDGE FLYSFTIDNS
   121  TYSLFPQATP FQLPLKKCAV VGNGGILKKS GCGRQIDEAN FVMRCNLPPL SSEYTKDVGS
   181  KSQLVTANPS IIRQRFQNLL WSRKTFVDNM KIYNHSYIYM PAFSMKTGTE PSLRVYYTLS
   241  DVGANQTVLF ANPNFLRSIG KFWKSRGIHA KRLSTGLFLV SAALGLCEEV AIYGFWPFSV
   301  NMHEQPISHH YYDNVLPFSG FHAMPEEFLQ LWYLHKIGAL RMQLDPCEDT SLQPTS

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against ST8SIA1 can act on the native protein depends on physical access: surface and secreted proteins are reachable by circulating antibodies, intracellular proteins usually are not.

Antibody reachability
Other membrane
Secreted
No
Transmembrane segments
1
Mean surface accessibility (rSASA)
0.31
Highest tissue expression
6 nTPM

Expression across tissuesHPA

Tissue

  • cerebellum: 6 nTPM
  • parathyroid gland: 5.9 nTPM
  • retina: 5.6 nTPM
  • cerebral cortex: 4.9 nTPM
  • tonsil: 4.5 nTPM
  • hypothalamus: 4.4 nTPM

Single-cell type

  • bergmann glia: 486 nCPM
  • ependymal cells: 398 nCPM
  • oligodendrocyte progenitor cells: 336 nCPM
  • myosatellite cells: 267 nCPM
  • mast cells: 218 nCPM
  • astrocytes: 162 nCPM

Immune cell

  • T-reg: 0.8 nTPM
  • memory CD4 T-cell: 0.7 nTPM
  • memory CD8 T-cell: 0.6 nTPM
  • basophil: 0.3 nTPM
  • MAIT T-cell: 0.2 nTPM
  • naive CD8 T-cell: 0.2 nTPM

Brain region

  • cerebellum: 43 nTPM
  • medulla oblongata: 37 nTPM
  • hypothalamus: 34 nTPM
  • pons: 32 nTPM
  • midbrain: 32 nTPM
  • spinal cord: 31 nTPM

Genetic constraint and essentialitygnomAD · DepMap

Does the body need this protein intact? Low LOEUF or a strong DepMap dependency means loss or blockade of the protein is likely to be felt.

gnomAD LOEUF (loss-of-function intolerance)
0.53
gnomAD pLI
0.49
gnomAD missense Z
1.16
DepMap mean gene effect
-0.01
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 5% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads ST8SIA1 as an antibody target. Whether an autoantibody or antibody against ST8SIA1 could matter depends on whether native ST8SIA1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

ST8SIA1 is annotated as predominantly intracellular. Intracellular proteins are common autoantibody markers, becoming visible to the immune system after cell injury or altered processing, but are usually markers of disease rather than direct drivers.

Annotation status

The present source text does not explicitly label ST8SIA1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/ST8SIA1. Study-independent annotations aggregated from UniProt, Human Protein Atlas, PubMed, IEDB, Pfam, InterPro, Gene Ontology, AlphaFold, gnomAD, DepMap, ClinVar, TCGA. Catalog release seroatlas-reviewed-human-uniprot-20260313.

Seroatlas is the reference for exploring autoantibody and antibody serology at the human-protein level: the autoreactome and human serome, multiplex serology (HuProt, HuScan, VirScan, PhIP-Seq).

© 2026 · Seroatlas, Discover Oregon LLC · Terms of use

Loading the interactive Seroatlas protein explorer...